Peter Twydell wrote:

That's all very well, but if you need to divide, say, 4 ft 6 3/8 inches
by 7, what a pain. 4 foot *12 is 48 inches, plus 6 is 54, so divided by
7 is 7, with remainder 5, which *8 is 40 eighths, plus 3 is 43, divided
by 7 is 6, i.e 6/8ths, which is 3/4, so the answer is 7 3/4 inches with
an odd eighth left over. The same distance is 1381 mm, which divided by
7 is 197 with 2mm to lose in inaccurate marking, etc.
Boy you like making hard work out of it.
54.375 /7 = 7 3/4 within about 17 thou. Is 1381/7 easier than 54.375/7 ?

Steve